Th1 Cytokine Pattern Research Articles

Mouse cytokine profiles associated with Brucella abortus RB51 vaccination or B. abortus 2308 infection.

This study indicated that mice immunized with Brucella abortus RB51 bacteria and subsequently challenged with B. abortus 2308 were protected from reinfection. After vaccination, both Th1 and Th2 cytokine patterns were observed. Of those, the early production of gamma interferon seems to have the prominent role in inducing an immunologically based protection.

Epidemiology, clinical features, and immunology of the "intrinsic" (non-IgE-mediated) type of atopic dermatitis (constitutional dermatitis).

Departmentof Pharmacology, University of Bern, Bern, SwitzerlandKey words: atopic dermatitis; clinical features;constitutional dermatitis; epidemiology; extrinsictype; immunopathology; intrinsic type.Prof. Dr B. Wu¨thrichAllergy Unit, Department of DermatologyUniversity Hospital8091 ZurichSwitzerlandAccepted for publication 22 March 2001

Differentiation of Resting Human Peripheral Blood γδ T Cells toward Th1- or Th2-Phenotype

Depending on the microenvironment, murine γδ T cells differentiate into either Th1 (IFN-γ-producing) or Th2 (IL-4-producing) cells. It is unclear, however, whether circulating human peripheral blood γδ T cells can be driven into Th1 or Th2 cells by modulation of the priming cytokine milieu. In this study, peripheral blood γδ T cells were stimulated by phosphoantigen (isopentenyl pyrophosphate) or Daudi lymphoma cells in the presence of Th1-priming (rIL-12, anti-IL-4 Ab) or Th2-priming (rIL-4, anti-IL-12 Ab) conditions. Single-cell analysis of cytokine secretion (IFN-γ and IL-4) was performed by flow cytometry after 18 h and after restimulation of expanded γδ T cells. The early activation of resting γδ T cells was characterized by the induction of IFN-γ. Priming under Th1 conditions induced a Th1 profile characterized by increased secretion of IFN-γ and TNF-α, while Th2 conditions caused increased production of IL-4 (Th2 profile) by the γδ T cells. These results indicate that the major subset of human γδ T cells can be polarized into either Th1 or Th2 cytokine pattern depending on the cytokine milieu in which contact with antigen occurs.

Cytokine gene polymorphisms relevant for the spondyloarthropathies.

Results of sibling and twin studies suggest that a substantial proportion of susceptibility to spondyloarthropathies arises from genes outside the human leukocyte antigen (HLA) region. There is increasing evidence that the pattern of cytokine secretion influences the course of spondyloarthropathies. A Th2 cytokine pattern (low tumor necrosis factor [TNF]-TNF-alpha low interferon [IFN]-gamma, and high interleukin [IL]-10) dominates in the joints of reactive arthritis patients. For IL-10 and TNF-alpha a substantial proportion of cytokine production is under genetic control and influenced by genetic polymorphisms. Here we review the evidences for association of TNF-alpha and IL-10 polymorphisms with spondyloarthropathies and their functional implications.

Allergen-induced changes in airway responsiveness are not related to indices of airway edema

Background: The mechanisms behind airway hyperresponsiveness in asthma are unknown. Airway wall edema has been proposed as one possible culprit of this phenomenon. Objective: To test the hypothesis that airway edema may be the cause of allergen-induced increases in airway responsiveness in asthma, this trial aimed at determining the relationship between allergen-induced changes in airway responsiveness to inhaled methacholine and indirect indices of edema, namely peripheral airway resistance and the levels of the plasma protein fibrinogen in bronchoalveolar lavage (BAL) fluids. Methods: Twenty-six atopic individuals with mild asthma were subjected to bronchoscopy at baseline and 28 hours after allergen inhalation. Before each bronchoscopy, methacholine bronchoprovocation was performed. During bronchoscopy, peripheral airway resistance measurements were obtained by wedged bronchoscopy. BAL fluids were analyzed for fibrinogen, as well as for eosinophilic cationic protein. Cytology was performed, and cytokine gene expression was assessed with competitive reverse transcriptase PCR from cell pellets. Results: A significant increase in airway responsiveness to methacholine was recorded after allergen, but this did not correlate with changes in peripheral airway resistance (which was not affected) or with BAL fibrinogen (which decreased after allergen). Other BAL outcomes confirmed that airway inflammation was produced and was characterized by a TH2 cytokine pattern. Conclusions: Airway responsiveness in asthma increases after exposure to allergen in the absence of increased indirect indices of edema. The role of edema in this phenomenon should therefore be tested more vigorously. (J Allergy Clin Immunol 2001;107:805-11.)

Fas-FasL interaction modulates nitric oxide production in Trypanosoma cruzi-infected mice.

During acute Trypanosoma cruzi infection in mice, many leucocytes undergo apoptosis. Although apoptosis has been ascribed to increased levels of nitric oxide (NO) and Fas-FasL interaction, the importance of this phenomenon in modulating the host response against T. cruzi is unknown. Herein, the role of NO- and Fas-FasL-induced apoptosis in modulating the immune response to T. cruzi was evaluated using mice deficient in Fas expression (MRL/MpJ-Fas lpr) and inducible nitric oxide synthase (iNOS) knockout mice (iNOS-/-). The results showed that besides decreasing apoptosis induction after infection, impairment of the Fas-FasL interaction resulted in decreased NO production, as a consequence of enhanced T helper 2 (Th2) cytokine production. Differently, blockage of NO-induced apoptosis resulted in uncontrolled cytokine production, rather than a biased Th2 cytokine pattern. Together, these results suggested that Fas and FasL-induced apoptosis could be implied in modulation of the immune response against T. cruzi by interfering with cytokine and NO production during the acute phase of the infection.

A rapid flow cytometric assay to detect CD4+ and CD8+ T-helper (Th) 0, Th1 and Th2 cells in whole blood and its application to study cytokine levels in atopic dermatitis before and after cyclosporin therapy.

The immune response in atopic dermatitis (AD) is thought to be driven by T-helper (Th) 2 cytokines. Using flow cytometry, higher frequencies of peripheral blood CD4+ and CD8+ T cells producing interleukin (IL)-4 and correspondingly lower frequencies of CD4+ T cells producing interferon (IFN)-gamma have been found in patients with AD compared with healthy controls. It would be of interest to know whether other Th1 and Th2 cytokines such as IL-5, IL-13 and tumour necrosis factor (TNF)-alpha are similarly skewed in patients with AD and whether this immune skewing, detected via a simple blood assay, can be correlated with other clinical measurements or treatments in AD. To use a rapid (4-h) flow cytometric assay to study a wide range of Th1 and Th2 cytokine patterns in peripheral blood lymphocytes from patients with AD, comparing them with non-atopic healthy controls. To correlate cytokine patterns with the degree of eosinophilia observed and in the case of one patient with severe disease, to observe the effect of cyclosporin therapy on peripheral blood cytokine patterns. Peripheral blood from eight patients with AD and 23 healthy controls was examined for the frequencies of CD4+ and CD8+ T cells expressing IL-2, IL-4, IL-5, IL-13, IFN-gamma and TNF-alpha using flow cytometry. Significantly higher frequencies of CD4+/IL-4+ (P < 0.005) and CD4+/IL-13+ (P < 0.0001) and lower frequencies of CD4+/IFN-gamma+ (P < 0.002) and CD8+/TNF-alpha+ (P < 0.05) T lymphocytes were found in patients with AD compared with controls. There were significant positive correlations with the increased percentages of CD4+/IL-4+ and CD4+/IL-13+ T lymphocytes and the degree of eosinophilia observed (P < 0.05, P < 0.001) and a negative correlation between the percentage of CD4+/IFN-gamma+ T lymphocytes and eosinophilia (P < 0.05). In one patient examined before and 8 days after cyclosporin therapy, 50% or greater reductions were observed in percentages of peripheral blood CD8+/IL-5+, CD8+/IL-13+, CD4+/IL-4+ and CD4+/IL-5+ T lymphocytes following cyclosporin therapy. A smaller reduction of 15% after cyclosporin therapy was found in percentages of CD4+/IL-13+ T cells. These data strongly support a Th2 predominance in the peripheral blood of AD. The results suggest that administration of cyclosporin therapy in patients with AD may help to restore the Th2 cytokine imbalance seen in these patients.

Peripheral blood stem cell transplantation in multiple sclerosis with busulfan and cyclophosphamide conditioning: Report of toxicity and immunological monitoring

Multiple sclerosis (MS) is an immune-mediated disease that may be amenable to high-dose immunosuppression with peripheral blood stem cell transplantation (SCT) in selected patients. Five MS patients (all women, ages 39-47 years) received granulocyte colony-stimulating factor (G-CSF) for stem cell mobilization, CD34 cell selection for T-cell depletion, a preparatory regimen of busulfan (1 mg/kg x 16 doses) and cyclophosphamide (120 mg/kg), and antithymocyte globulin (10 mg/kg x 3 doses) at the time of stem cell infusion. Days required to recover absolute neutrophil count >500 were 12 to 14 and platelet count >20,000 were 17 to 58. Posttransplantation infectious complications in the first year after SCT occurred in 3 of 5 patients, and 1 patient died at day 22 after SCT from influenza A pneumonia. Neuropathologic study in this patient showed demyelinating plaques with surrounding macrophages but only rare T cells. In 2 patients, MS flared transiently with G-CSF. Magnetic resonance imaging gadolinium enhancement was present in 3 of 5 patients before transplantation and 0 of 4 after SCT. There were cerebrospinal fluid oligoclonal bands at 1 year after SCT, similar to the pretransplantation assays. Sustained suppression of peripheral blood mononuclear cell proliferative responses to myelin antigens occurred after SCT, but new responses to some myelin peptide fragments also developed after SCT. In 1 patient, enzyme-linked immunospot (ELISPOT) assays done 9 months after SCT showed a predominant T helper 2 (Th2) cytokine pattern. Neurological progression of 1 point on the extended disability status scale was seen in 1 patient 17 months after SCT. Another patient who was neurologically stable died abruptly 19 months after SCT from overwhelming S. pneumoniae sepsis. The remaining patients have had stable MS (follow-up, 18 and 30 months). In summary, our experience confirms the high-risk nature of this approach. Further studies and longer follow-up would be needed to determine the significance of new lymphocyte proliferative responses after SCT and the overall effect of this treatment on the natural history of MS. Biol Blood Marrow Transplant 2000;6(5A):563-75.

Mechanisms of allergen-specific immunotherapy.

Mechanisms of allergen-specific immunotherapy.

Immune responses during the acute stages of infection with the intestinal trematode Echinostoma caproni.

This study investigated the nature of the immune response of C57BL/6 mice infected with the trematode Echinostoma caproni. To determine the preferential development of either a Th1 or Th2 cytokine pattern during early stages of infection, cytokine production by spleen and mesenteric lymph node (MLN) cells during the first 3 weeks of infection was followed. Whereas spleen cells failed to respond to antigen stimulation, MLN cells produced IFN-gamma and to a lesser extent IL-4. IL-5 levels were elevated throughout the period studied. The humoral response was consistent with a Th1 cytokine pattern as antigen-specific IgG2a antibodies were preferentially developed. We investigated whether IFN-gamma is critical for establishment of E. caproni infection. Worm burden in infected mice treated with a single injection of anti-IFN-gamma mAb was significantly reduced compared to that of animals treated with a control antibody.

Incomplete Freund's adjuvant reduces diabetes in the non-obese diabetic mouse.

As the study of type 1 diabetes moves towards preventive therapy, the role of adjuvants needs to be addressed. Incomplete Freund's adjuvant (IFA) is thought of as "immunologically inert" as, unlike complete FA (CFA), it has no components designed to provoke an immune response. We investigated the effect of IFA as an immunomodulator on the disease process leading to type 1 diabetes in the non-obese diabetic (NOD) mouse. 24 NOD mice were injected intradermally (i.d.) at 8 and 12 weeks of age with a 1:1 mixture of IFA and saline; 24 controls received saline alone. Splenocytes were tested against antigens thought to be involved in the disease process, namely insulin, a GAD peptide, a beta-casein peptide, a Glut-2 peptide and concanavalin A (ConA) as a non-specific antigen. In the IFA experiment diabetes incidence was 13% compared to 38% in the controls (p < 0.05). In vitro, splenocytes from IFA treated animals showed non-specific immunosuppression with ConA (p < 0.01), whereas the response to 1-casein and Glut-2 was raised in IFA treated animals with respect to controls. ELISA using supernatants from IFA treated animals, showed a typical Th2 cytokine pattern, whereas controls showed a Th1 pattern. In conclusion, IFA alone can reduce diabetes incidence in the NOD mouse apparently by modulating the immune response towards beta-cell related specific antigens. As IFA has been adopted as an adjuvant in preventive trials in the NOD mouse, this might have implications for the interpretation of previous and future results.

Antigen-Dependent Cytokine mRNA Expression by Individual Rhesus Macaque T Helper Cells by Flow Cytometry

Specific patterns of cytokine secretion by CD4+ T helper (Th) cells determine the nature of immune effector responses. Using a multiparameter, flow cytometric fluorescent in situ hybridization (FISH) assay that detected cytoplasmic mRNA within intact cells, we assessed antigen-specific cytokine expression in rhesus macaque Th cells. In the peripheral lymphocytes of immunized rhesus macaques, FISH detected antigen-induced cytokine gene expression in single Th cells. Analysis of simultaneous cytokine expression by single cells demonstrated that the recall immune response consisted of Th cells expressing either a Th1 (IL-2+/IFN-γ+) or a Th2 (IL-4+/IL-6+) cytokine pattern. In addition to the classic Th subsets, Th cells expressing only one of two Th1 or Th2 defining cytokines were common following antigen restimulation. The data gathered with the FISH assay suggest that, in primates, the immune response to recall antigens consists of nonclassic Th cells, as well as a mixture of polarized Th1 and Th2 T cells.

Evidence for human CD4+ T cells in the CD1-restricted repertoire: derivation of mycobacteria-reactive T cells from leprosy lesions.

Both the CD4-CD8- (double negative) and CD4-CD8+ T cell lineages have been shown to contain T cells which recognize microbial lipid and glycolipid Ags in the context of human CD1 molecules. To determine whether T cells expressing the CD4 coreceptor could recognize Ag in the context of CD1, we derived CD4+ T cell lines from the lesions of leprosy patients. We identified three CD4+ Mycobacterium leprae-reactive, CD1-restricted T cell lines: two CD1b restricted and one CD1c restricted. These T cell lines recognize mycobacterial Ags, one of which has not been previously described for CD1-restricted T cells. The response of CD4+ CD1-restricted T cells, unlike MHC class II-restricted T cells, was not inhibited by anti-CD4 mAb, suggesting that the CD4 coreceptor does not impact positive or negative selection of CD1-restricted T cells. The CD4+ CD1-restricted T cell lines produced IFN-gamma and GM-CSF, the Th1 pattern of cytokines required for cell-mediated immunity against intracellular pathogens, but no detectable IL-4. The existence of CD4+ CD1-restricted T cells that produce a Th1 cytokine pattern suggests a contributory role in immunity to mycobacterial infection.

Th1/Th2 lymphocyte polarization in asthma.

Asthma is a complex inflammatory disease of the lung characterized by variable airflow obstruction, bronchial hyperresponsiveness, and airway inflammation. Inflammation in asthma consists of airway infiltration by mast cells, lymphocytes, and eosinophils. There is accumulating evidence that CD4+ lymphocytes with a Th2-cytokine pattern play a pivotal role in the pathogenesis of asthma. These cells orchestrate the recruitment and activation of the primary effector cells of the allergic response (mast cells and eosinophils), through the release of cytokines such as IL-4, IL-5, and IL-13. Allergic inflammation is also implicated in airway epithelium changes, although the mechanisms by which inflammatory cells and, in particular, T cells interact with the epithelium are not completely clarified. This paper explores the role of T cells in the allergic inflammation of asthma.

Protective DNA immunization against Chlamydia pneumoniae.

We have investigated the efficacy of the DNA vaccination using the heat shock protein 60 (HSP-60) gene of C. pneumoniae, for protection of mice against infection with the bacteria. C57Bl/6 mice had a 5-20-fold reduction of C. pneumoniae numbers in lungs when immunized intranasally (i.n.) with plasmids (p) encoding pHSP-60. The reduction of the bacterial load coincided with a decreased severity of disease. No specific antibodies were detected after protective i. n. immunization. In contrast, mice immunized intradermally (i.d.) were not protected against challenge with C. pneumoniae, although specific humoral Immunoglobulin (Ig)G responses were generated. Co-inoculation i.n. of pHSP-60 with pIL-12 but not with pGM-CSF further increased protection of mice against infection with C. pneumoniae. Lungs from pHSP-60 i.n. immunized and infected mice showed higher levels of interferon (IFN)-gamma mRNA, and spleen cells from these mice co-cultured with r-HSP-60 released higher levels of IFN-gamma and displayed higher proliferative responses than nonimmunized and infected controls. pHSP-60 immunized IFN-gamma receptor (R)-/- mice were not protected against infection with C. pneumoniae. Likewise, i.n. administration of pIFN-gamma alone induced significant protection. DNA vaccine-induced protection was CD4+ and CD8+ T-cell dependent, as shown by DNA-vaccination of MHC class II-/-, CD4-/-, CD8-/- and CD4-/-CD8-/-mice. Interestingly, DNA vaccine induced CD4+ T cells, in the absence of CD8+ T cells, were involved in worsening the outcome of infection. This worsening was linked with a shift towards a Th2 cytokine pattern.

473 Asp f 2 T cell clones from ABPA patients show both Th1 and Th2 cytokine patterns

473 Asp f 2 T cell clones from ABPA patients show both Th1 and Th2 cytokine patterns

Feedback mechanisms between T helper cells and macrophages in the determination of the immune response

The interactions between macrophages and T helper (Th) cells are a complex interplay of positive and negative signals. Some of the mathematical models of interactions between T helpers have indeed taken the influence of macrophages into account. In this work the macrophage is not considered as an extrinsic agent, that is duly directed by the T cells to be cytotoxic, nor is there consideration of T helper cell populations that are dominantly regulated by extrinsic properties of antigens per se, or by certain classes of presenting cells that preferentially select certain classes of lymphocytes or bias their commitment. Rather, a simplified model of feedback loops between Th cells and macrophages is formulated and analyzed. It is suggested how the mutual influence between Th and macrophages can determine the cytokine secretion pattern of these populations. The model provides a feedback scenario to account for experimental findings concerning reversal in the dominance of a specific cytokine profile in the course of some infections. A possible scenario accounting for the difference between the stability of Th1 and Th2 cytokine pattern is put forward. The model suggests explanations for the variability in the outcome of the immune response according to different body compartments. A rationale is presented that accounts for paradoxical findings indicating that Th1 cytokines are sometimes responsible for the downregulation of a Th1 dominated response.

Intracytoplasmic Th1 and Th2 Cytokines in Rheumatoid Arthritis Blood and Synovial Tissue

In rheumatoid arthritis (RA), T cells have been proposed either as a main actor or as an epiphenomenon in such a primarily synoviocyte-driven disease. A major issue remains the remarkable paradox between the T cell infiltrate and the relative failure to detect definite markers of their activity. To determine the Th1/Th2 cytokine profile in RA synovium, we used a single cell flow cytometric assay for interleukin-2 (IL-2), interferon-γ (IFN-γ), IL-4 and IL-10 in paired peripheral blood (PB) and synovial tissue (ST) lymphocytes from RA and osteoarthritis (OA) patients and PB lymphocytes from healthy controls. Cytokines were undetectable in unstimulated PB and ST lymphocytes. More stimulated PB and ST CD4+lymphocytes produced IFN-γ than IL-4, for all individuals tested. RA PB CD4+lymphocytes showed the same Th1 cytokine pattern as normal controls. No increase of such a Th1 profile was observed for ST lymphocytes. A specific recruitment of T CD4+lymphocytes in the rheumatoid inflamed synovium could not be concluded on the basis of these results.

Th1 cytokine patterns in cervical human papillomavirus infection.

The host's immune response to cervical human papillomavirus (HPV) infection is poorly understood. In a longitudinal cohort of women with cervical HPV infections, defined by PCR-based HPV DNA testing, we used exfoliated cervical cells and reverse transcription-PCR to examine the cervical mucosal mRNA expression of cytokines involved in regulating cell-mediated immunity. We identified seven HPV-positive subjects who were found to have cleared their HPV infections 4 months later. In all seven, a T-helper type 1 (Th1) cytokine pattern (expression of gamma interferon and absence of interleukin-4) preceded clearance. The more variable cytokine patterns seen in HPV-negative subjects suggest that the Th1 pattern in the women with subsequent clearance was a response to the HPV infection. This contention is supported by additional cross-sectional data showing a Th1 pattern in a majority of HPV-positive women. This study establishes a feasible means for assessing local cytokine expression in the cervical milieu and demonstrates that a Th1 cytokine response is associated with subsequent clearance of cervical HPV infection.

Differential expression of B7 co-stimulatory molecules by astrocytes correlates with T cell activation and cytokine production.

Whether astrocytes utilize B7:CD28 co-stimulation to activate T cells mediating CNS inflammatory disease is controversial. In this report, primary astrocytes and murine astrocyte lines, generated by immortalization at two different times, day 7 or 45 of culture, were examined for their capability to express B7 co-stimulatory molecules and to participate in B7:CD28 co-stimulation. Following exposure to IFN-gamma, primary astrocytes and astrocyte lines up-regulated MHC class II and B7-2 (CD86) molecules. However, B7-1 (CD80) expression was not inducible on primary astrocytes examined after IFN-gamma stimulation beginning on day 7 or on astrocyte lines immortalized on day 7. B7-1 expression was inducible on primary astrocytes examined later and could be up-regulated on astrocyte lines immortalized later. Unlike B7-1, temporal discordant expression of other co-stimulatory/adhesion molecules was not observed. Both B7-1(-)/B7-2(+) and B7-1(+)/B7-2(+) astrocyte lines were capable of stimulating proliferation of encephalitogenic Th1 cells, utilizing B7-2 for B7:CD28 co-stimulation. However, lines derived from immortalization later (B7-1(+)/B7-2(+)) were more effective in stimulating proliferation of naive myelin basic protein-specific CD4(+) T cells. Astrocyte lines that expressed both B7-1 and B7-2 also stimulated Thp cells to secrete proinflammatory Th1 cytokines, whereas lines that expressed B7-2 only stimulated Thp cells to produce a Th2 cytokine pattern. Thus, we demonstrate for the first time that individual astrocytes can differentially express B7-1 molecules, which may correlate with their ability to stimulate proinflammatory and regulatory patterns of cytokine production. These results suggest that astrocytes have potential for both promoting and down-regulating T cell responses, and that temporal differences in expression of B7 molecules should be considered when evaluating immune regulation by astrocytes.